Typo??? You meantno pentration right?

I agree the bullet is most likely not the problem it was placement. 130/277 bullet at relatively close range was moving beyond the design limts of the bullet, add to that the resistance met by bone structurecausedit to over expand, frag and reduce pentration. However you never said exactly where the hit, just low so I assumed it was near the brisket which offers substantial resistance.I have seen far more shooter failures then bullets...based on the info given it seemed like a good assumption.

FWIW I have actually seen 2 corelokt potential failuresboth came apartand afiled to penetrate.1 was a 3006 150gr on a whitetail buck, & the other was 338wm 225gr on a spike bull elk. Both animals were recovered but they did manage to make us dig out the tracking skills. I say potential as I wasn't the shooter, so only went on the guys who relayed the story and evidence in form of the carcasses. In regards to the elk it certainly appeared that the bullet deflected which indicatesmay nothave been asbroadside as the shooter remembers. The other it looked like he had been hitt by a sledgehammer - pretty sure this deer was perfectly broadside and a bullet failure occurred. Neither were really close and the only bonetouched was entrance side ribs.